• THE INFLUENCE OF CARBONIC ACID AMMONIUM SALTS ON THE FILTRATION PROPERTIES OF BOTTOM-HOLE FORMATION ZONE

Abstract

The possibility of using ammonium carbonates to increase hydrocarbons extraction is considered. To study the effect of ammonium carbonate salts on the reservoir filtration properties a complex of experimental studies has been carried out. It has been established that carbon dioxide ammonium salts, in the absence of calcium chloride water, interact with carbonate rocks, increase the absolute permeability of reservoirs. The solutions of ammonium carbonate salts interact with calcium chloride type of formation water and form chemically precipitated chalk in the pores of the rock. Herewith the permeability of carbonate rocks decreases. The industrial tests of ammonium carbonate salts have shown an increase in gas flow rate by 30-50% at wells № 23 of Opishnyanske, № 115 of Mashivske, № 3 of Tymofiyivske gas condensate fields. The effect of the ammonium carbonates treatment of the formation is stipulated by the purification of the bottom-hole formation zone and an increase of the absolute permeability of the reservoirs. The increase of the condensation factor by 22-35% has been observed in wells № 56, 108 of Yablunivske and № 58 of Tymofiyivske gas condensate fields. The efficiency of the treatment is related to the simultaneous purification of the bottom-hole zone from asphalt-resinous contaminants and to the absolute permeability increase, as well as to the pore space hydrophilization and the increase in the mobility of condensate that has fallen due to the influence of carbon dioxide which generates as a result of the decomposition of carbonic acid ammonium salts. Thus, pilot tests at Opishnyanske, Mashivske, Tymofiyivske, Yablunsvske gas condensate fields of Poltava region confirmed the effectiveness of using ammonium carbonate salts to increase hydrocarbon production. The prospect of further research is aimed at developing a technology for increasing the liquid hydrocarbons production by the use of ammonium carbonate salts.